In respect of a wide range of industrial applications, including but by no means limited to applications in open cast mining and quarrying, there is often a requirement to make use of heavy plant or apparatus at a first working location for a period of time, which then requires moving to another working location. Where such apparatus or plant is moved only occasionally, with long intervening periods of static operation, it is not likely to be necessary to make it fully mobile by provision of an integral transport system. Instead, it is typical to use an external transporter to move the apparatus as and when required.
A typical transporter may comprise a supporting chassis or body provided with ground contacting transport means, such as in a typical case a pair of crawler tracks, and having a support apparatus on which a payload comprising such apparatus or plant to be moved can be carried.
In a typical mode of operation, a support apparatus is provided which can be raised and lowered. This may for example be in the form of a payload support platform with suitable means to raise and lower it and thus raise and lower the payload. At its lowered configuration, the transporter may be driven into a position underneath the apparatus to be moved. The platform or other support apparatus is then raised to support the apparatus to be moved above the ground, and the transporter is driven to move the apparatus. The support platform may be raised, lowered and tilted by suitable extending shafts, pistons or the like.
The payloads carried by such transporters are typically very heavy. The terrain over which the payloads are transported can be rough, and include significant undulations and gradients. The payload needs to be lifted clear of such rough terrain to be transported, but the resultant arrangement is potentially top-heavy and unstable. The safe and stable support of the payload during lifting and transportation is a significant concern. In particular, if the payload centre of gravity is off centre, the effect of ground undulations and gradients can be exaggerated to impart significant torque on any shafts, pistons or the like that raise or lower the platform. Slewing operation is typically impractical. Instead transporters may effect a static turn or may be required to drop the payload, move, and then reload.